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Assessment of Vehicle Fire Development in Road Tunnels for Smoke Control Ventilation DesignCheong, Mun Kit January 2009 (has links)
A fire in road tunnel can be dangerous and lead to serious consequences if not addressed
appropriately. In a tunnel fire incident, creating a smoke free path for motorist evacuation
and facilitating fire fighters to access the fire is critical for fire and rescue operations. A
means of achieving this is to use ventilation fans to blow sufficient air down the tunnel
ensuring no back-layering of smoke occurs upstream of the fire. The airflow necessary for
such operation is known as the critical velocity which is a function of a number of factors
includes; heat release rate, tunnel geometry, tunnel gradient etc. Among these parameters,
the heat release rate is the most difficult to identify as this value is dependent on the types
of vehicles, number of vehicles involved, the type of cargo and the quantity of cargo
carried by these vehicles. There are also other factors such as the influence of ventilation
condition, tunnel geometry and the use of legislation (to restrict hazardous vehicles
entering in tunnel) that could affect the heat release rate in a tunnel fire. The number of
possible fire scenarios is numerous.
Based on current practise, fire size selection for most tunnel ventilation design often
references various guidelines such as NFPA 502, BD78/99 or the PIARC technical
committee report. The heat release rate, particularly for goods vehicle recommended by
the guidelines varies from 20 to 30 MW. However, recent fire tests conducted in the
Runehamar tunnel experiments indicate a higher heat release rate. These experiments
suggest that heat release rate guidelines for goods vehicles might be underestimated. An
ideal means to estimate the heat release rate in the tunnel is to use the oxygen consumption
calorimetry technique. However, this approach is generally expensive, logistically
complicated to perform and it is often not feasible to conduct such tests for a tunnel project
at the initial design stage simply because the structure and systems are not ready for such
activities.
This research thesis presents an approach to establish a design fire in a road tunnel
particularly the peak heat release rate for emergency tunnel ventilation system design. The
analysis consists of two stages; stage one involves the use of a probabilistic approach (risk
analysis) to identify the potential cause and type of vehicle which could result in a tunnel
fire. Findings from the risk analysis are used in stage two in which Computational Fluid
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Dynamics (CDF) modelling is used to establish the heat release rate in the tunnel
considering factors such as fuel load, ventilation condition, tunnel geometry and ignition
location. The Fire Dynamics Simulator (FDS 4.0.7), a CFD model of fire-driven fluid flow
is used for the analysis and an urban road tunnel project in Singapore is used to illustrate
this methodology.
Other topic related to this research work includes the reconstruction for the Runehamar
tunnel fire test using numerical approach to calibrate the FDS simulation model. The used
of Probabilistic Bayesian approach and CFD approach using FDS to estimate the heat
release rate in the tunnel is also investigated in this thesis. The effect of vehicle fire spread
in road tunnel and numerical simulation of road tunnel fires using parallel processing is
presented. Preliminary work in using FDS5 for tunnel simulation work is discussed as part
of the research work in this project.
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Pollutant profiles as tools for characterisation of environmental exposureWingfors, Håkan January 2004 (has links)
This thesis is concerned with measurements of persistent organic pollutants (POPs) in environmental samples. The POPs consist of several groups of compound with many isomers, hence analysing POPs in a complex environment is a This thesis is concerned with measurements of persistent organic pollutants (POPs) in environmental samples. The POPs consist of several groups of compound with many isomers, hence analysing POPs in a complex environment is a challenging task. Studies of the abundance or dynamics of such substances in the environment require careful consideration of several key steps. The environmental and analytical problems must be correctly defined, suitable analytes, sampling strategies and techniques must be selected, the chemical analyses must be reproducible and accurate, and the data evaluation protocols must be rigorous and appropriate. The aim of this thesis was to evaluate the use of pollutant profiles in order to assess complex patterns of environmental exposure. When combined with multivariate data analysis (MVDA) a maximum of information may be extracted from analytical data. Nevertheless, good quality data is essential for correct evaluation of the environmental phenomena under investigation. The precision and accuracy of a solid phase assisted liquid extraction method was therefore assessed by comparison to a reference method. The validated method was used in two human exposure studies. The concentrations of PCBs and dioxins were determined in human tissues from general populations in Sweden and Spain. Although it was concluded that the populations were exposed to similar degree to PCBs and dioxins, principal component analysis (PCA) showed that the compound profiles differed between the populations. PCA was also used to differentiate between occupationally exposed workers and matched controls and between exposed workers with recent and earlier exposure. In addition, the analysis indicated that the differences in PCB patterns in workers with recent and earlier exposure were related to differences in the metabolic degradation rates of individual PCBs. The PCA model was further used to select PCB congeners that were representative of each group. Finally, the emission of polycyclic aromatic hydrocarbons (PAHs) in a traffic tunnel was estimated by measuring 29 individual PAHs. The sampling periods were chosen to reflect a maximum variation in the traffic composition. An excellent prediction of the percentage of heavy-duty vehicles was obtained using partial least squares (PLS) regression. It was shown by PCA that it might be possible to predict source compositions at other locations with the aid of multivariate statistical tools. Thus, properly gathered pollutant profiles and MVDA may be combined to extract a large amount of significant information from environmental source and exposure data.
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Προσδιορισμός φυσικών ιδιοτήτων στους μαργαϊκούς σχηματισμούς της οδικής σήραγγας ΠλατάνουΤσιμικλής, Δημήτριος 07 October 2011 (has links)
Στην εργασία αυτή καταγράφονται οι τεχνικογεωλογικές συνθήκες κατά τη διάνοιξη
Δίδυμης οδικής σήραγγας Πλατάνου μήκους 1630m η κατεύθυνση προς Αθήνα, 1570m η κατεύθυνση προς Πάτρα.
Η διάτρηση πραγματοποιείται μέσα σε μεταλπικά ιζήματα του νεογενούς. Ειδικότερα σε στιφρές μάργες με ενστρώσεις χαλαρών κροκαλοπαγών. Λόγω της φύσης των υλικών ήταν απαραίτητη η χρήση δοκών προπορείας, αγκυρίων προπορείας και μέσων προσωρινής αντιστήριξης (πλαίσια, εκτοξευόμενο σκυρόδεμα, αγκύρια, πλέγμα) και στα σημεία με έντονη υδροφορία έγινε χρήση μεμβρανών και συστηματικές αποστραγγιστικές οπές.
Η έρευνα εντοπίζεται στο σχηματισμό του κατώτερου ορίζοντα των Νεογενών και συγκεκριμένα στους σχηματισμούς των μαργολίθων – ιλυολίθων οι οποίοι παρουσιάζουν συμπεριφορά σκληρών εδαφών – μαλακών βράχων και φιλοξενούν το μεγαλύτερο τμήμα της σήραγγας.
Έγινε συστηματική δειγματοληψία στα μέτωπα εκσκαφής με τη μορφή δειγμάτων μεγάλων διαστάσεων (block samples) που μεταφέρονταν αμέσως στο εργαστήριο όπου και γινόταν γρήγορα ο προσδιορισμός των φυσικών ιδιοτήτων τους καθώς και η προετοιμασία για προσδιορισμό του δείκτη χαλάρωσης.
Στα δείγματα που διαμορφώθηκαν έγιναν δοκιμές προσδιορισμού των φυσικών ιδιοτήτων και συγκεκριμένα έγιναν οι παρακάτω δοκιμές: δοκιμές φυσικής υγρασίας, προσδιορισμός των ορίων συνεκτικότητας (όρια Atterberg), προσδιορισμός του ειδικού βάρους υλικού λεπτότερου υλικού των 2mm, κοκκομετρική ανάλυση με κόσκινα αλλά και με αραιόμετρο (μέθοδος Stoke’s), προσδιορισμός φαινόμενου βάρους συνεκτικών υλικών, προσδιορισμός του δείκτη χαλάρωσης πετρώματος και τέλος ο προσδιορισμός της αντοχής σε τριαξονική θλίψη σε αστράγγιστες συνθήκες φόρτισης (UU). / Determination of physical properties in the marly formations of the road tunnel Platanos. Laboratory tests made in laboratory engineering geology to explore the physical properties of the ash loam tunnel Platanos.
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Τεχνικογεωλογικές συνθήκες κατά τη διάνοιξη της σήραγγας Πλατάνου του νέου αυτοκινητόδρομου Κορίνθου-Πατρών. Μηχανική συμπεριφορά των εκσκαπτόμενων μαργολίθων και προβλήματα κατά την Α΄ φάση διάνοιξηςΚαπώνη, Ευθυμία 14 February 2012 (has links)
Η παρούσα εργασία πραγματεύεται τη μελέτη της δίδυμης οδικής σήραγγας που κατασκευάζεται στον Πλάτανο Αχαΐας. Πρόκειται για σήραγγα η οποία αποτελεί μέρος του έργου του νέου αυτοκινητοδρόμου «Ελευσίνα – Κόρινθος – Πάτρα – Πύργος – Τσακώνα» και εντάσσεται στο τμήμα «Κόρινθος – Πάτρα». Η έρευνα εντοπίζεται στο σχηματισμό του κατώτερου ορίζοντα των Νεογενών, συγκεκριμένα στους σχηματισμούς των μαργολίθων, οι οποίοι φιλοξενούν το μεγαλύτερο τμήμα της σήραγγας παρουσιάζοντας συμπεριφορά «σκληρού εδάφους – μαλακού βράχου» και εστιάζει στην Α φάση διάνοιξης της σήραγγας.
Με βάση τη συγκέντρωση υπαρχόντων στοιχείων για την ευρύτερη περιοχή, εξετάζεται η γεωμορφολογία, η στρωματογραφία, η τεκτονική και η σεισμικότητα, καθώς επίσης παραθέτονται μετεωρολογικά στοιχεία και γίνεται αναφορά στα κατολισθητικά φαινόμενα.
Ο σχεδιασμός του έργου αναλύεται διεξοδικά, με στοιχεία που αφορούν στους τεχνικογεωλογικούς σχηματισμούς που συμμετέχουν, στη διάνοιξη και κατασκευή του, αλλά και στα τεχνικογεωλογικά προβλήματα που εντοπίζονται και τα μέτρα αντιστήριξης που χρειάστηκε να ληφθούν. Ακόμη, παρουσιάζονται τα αποτελέσματα των επί τόπου δοκιμών γεωτεχνικής που πραγματοποιήθηκαν.
Εξετάζονται με βάση τη διεθνή εμπειρία, οι σχηματισμοί που αναφέρονται ως “σκληρά εδάφη – μαλακοί βράχοι” και ανήκουν στη μεταβατική ζώνη ανάμεσα στα εδάφη και τους βράχους, όσον αφορά στην κλίμακα αντοχής των γεωλογικών σχηματισμών. Σχολιάζεται η συμπεριφορά τους στα τεχνικά έργα και γίνεται περαιτέρω αναφορά, ειδικότερα για τους σχηματισμούς μαργολίθων - ιλυολίθων.
Βασικό στοιχείο της έρευνας αποτέλεσε η διερεύνηση των φυσικών και μηχανικών ιδιοτήτων των μαργών - μαργολίθων της σήραγγας. Για τον σκοπό αυτό, έγινε συστηματική λήψη δειγμάτων μεγάλων διαστάσεων (block samples) από τα μέτωπα εκσκαφής της Α φάσης, από τη Χ.Θ. 68 + 208 έως τη Χ.Θ. 68 + 406. Μετά την επίπονη διαμόρφωση δειγμάτων με τη χρήση πρότυπων μεθοδολογιών, εκτελέστηκε σειρά δοκιμών στο Εργαστήριο Τεχνικής Γεωλογίας του Πανεπιστημίου Πατρών, οι οποίες παρουσιάζονται και σχολιάζονται, ενώ παρατίθενται και τα πλήρη στοιχεία που αφορούν στην εκτέλεσή τους.
Στα πλαίσια του στόχου της εμπεριστατωμένης ανάλυσης και της απόδοσης μιας ολοκληρωμένης εικόνας των συγκεκριμένων μαργαϊκών σχηματισμών, γίνεται προσπάθεια συσχετισμού των εργαστηριακών παραμέτρων, ώστε να διαφανούν πιθανές εξαρτήσεις τους μέσω εμπειρικών σχέσεων γενικής εφαρμογής. / The present thesis treats of the study of the twin road tunnel of Platanos. This tunnel forms a part of the new “Elefsina - Corinth - Patras - Pyrgos - Tsakona” motorway and is integrated in the “Corinth - Patras” section. The research focuses on the formation of the lower horizon of the Neogenes, and, in particular, on the formations of marlstones, which surround the biggest part of the tunnel presenting a “hard soil - soft rock” behavior and focuses on the phase A of the excavation of the tunnel.
Based on collected data, the geomorphology, stratigraphy, tectonics and seismicity of the wider area are examined, meteorological elements are cited and landslide phenomena are pointed out.
The design of the project is thoroughly analyzed, along with data regarding the geotechnical formations of the area, its excavation and construction, as well as the geotechnical problems that are detected and the support measures needed to be taken. In addition, the results of the in situ geotechnical investigations are presented.
The formations known as “hard soil - soft rock”, that belong to the transitional zone between soil and rocks, are examined on the basis of international experience, as to the scale of their solidity. Their behavior as far as the structural works is concerned is commented and there is further reference regarding the marlstone - siltstone formations.
The investigation of the physical and mechanical properties of the tunnel marls constitutes the fundamental element of this research. For this purpose, systematic sampling of block samples has taken place from the excavation faces of phase Α, from CH 68 + 208 to CH 68 + 406.Subsequent to the arduous formulation of the samples using standard methodologies, a series of testings was carried out at the Laboratory of Engineering Geology of the University of Patras, which are presented and commented, whereas all the data concerning their execution are cited.
In the scope of a thorough analysis and the rendering of a comprehensive image of the marlstone formations, a correlation of all the data is attempted, in order to investigate any possible dependencies, through empirical relations of general application.
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Payback periods for photovoltaics integrated in nonbuilding structures / Återbetalningstider för solceller i anläggningskonstruktionerOlsson, Styrbjörn, Candler, Simon January 2019 (has links)
In order to provide Sweden and other countries across the globe with energy in a long-term and sustainable manner that accounts for our global environmental goals, we need to adopt more sources of renewable energy. Solar panels and other forms of solar power is one of these renewable energy sources that has a lot of potential and the technology has become increasingly more common in Sweden and other parts of the world in the latest decades. Everyone from private individuals to companies and authorities are increasingly making investments in the technology. With the help of our supervisors and after extensive literature studies we aim to increase the knowledge about solar panels and their economic aspects by calculating and presenting payback periods for solar panels implemented in nonbuilding structures. In conjunction with this we also aim to present a basic theoretical background about solar panels and their global impact to further the understanding of the technology even more. On behalf of, and in collaboration with Trafikverket we have examined the payback periods of four solar panel installations in connection to four of the authority´s nonbuilding structures. Three of these solar installations are applied on technical buildings that are scattered alongside the railway system across the country. The solar panels provide local electricity to the electrical components within the building. The fourth solar installation is connected to a road tunnel where it provides local electricity to the lights within the tunnel. The conducted calculations have resulted in a payback period for each respective solar installation measured in years based on various relevant factors that influence their energy production. Our hope is that this can clarify the economic aspects of the solar panels and be of help in potential future investments in solar power by Trafikverket. The conclusion is that the solar panel installation connected to the road tunnel has the shortest payback period by far and also has great potential to be economically lucrative by generating future revenue. The tree solar installations connected to the technical buildings each have a significantly longer payback period but are still expected to be paid back eventually. However they are not expected to generate a mentionable yield, if any. / För att vi ska kunna förse Sverige och resterande delar av världen med energi på ett långsiktigt och hållbart sätt som tar hänsyn till de globala miljömålen krävs det att vi börjar använda mer förnyelsebara energikällor. Solceller och solenergi är en av dessa energikällor som har stor potential och tekniken har under de senaste decennierna blivit allt vanligare både i Sverige och i andra delar av världen. Allt från privatpersoner till företag och myndigheter gör i större och större utsträckning investeringar i tekniken. Med hjälp av litteraturstudier samt stöd från handledare syftar denna avhandling till att öka kunskapen om solceller och deras ekonomiska aspekter genom att beräkna och presentera återbetalningstider för solceller implementerade i anläggningskonstruktioner. I samband med detta kommer en grundläggande teoretisk bakgrund om solceller samt deras globala påverkan att presenteras för att öka förståelsen för ämnet ytterligare. På uppdrag av och i samarbete med Trafikverket har återbetalningstiden för fyra solcellsinstallationer i anslutning till myndighetens anläggningar undersökts. Tre av dessa är teknikhus längs med järnvägen utspridda i olika delar av landet där solcellsinstallationen bidrar med elektricitet till de tekniska komponenterna i huset. Den fjärde installationen ligger i anslutning till en vägtunnel där solcellsinstallationen bidrar med elektricitet till belysningen i tunneln. Resultatet av beräkningarna har gett en återbetalningstid i år för respektive installation baserat på diverse relevanta parametrar som påverkar elproduktionen. Vår förhoppning är att detta kan klargöra de ekonomiska aspekterna av solcellerna samt underlätta för Trafikverket att ta beslut om framtida potentiella solcellsinvesteringar i anslutning till deras anläggningar. Slutsatsen är att solcellsinstallationen i anslutning till vägnätet har den överlägset kortaste återbetalningstiden samt även god potential att bli ekonomiskt lukrativ. De tre installationerna i anslutning till teknikhusen har betydligt längre återbetalningstid och anses så småningom bli återbetalda men utan någon nämnvärd avkastning, om ens någon.
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Payback periods for photovoltaics integrated in nonbuilding structures / Återbetalningstider för solceller i anläggningskonstruktionerOlsson, Styrbjörn, Candler, Simon January 2019 (has links)
In order to provide Sweden and other countries across the globe with energy in a long-term and sustainable manner that accounts for our global environmental goals, we need to adopt more sources of renewable energy. Solar panels and other forms of solar power is one of these renewable energy sources that has a lot of potential and the technology has become increasingly more common in Sweden and other parts of the world in the latest decades. Everyone from private individuals to companies and authorities are increasingly making investments in the technology. With the help of our supervisors and after extensive literature studies we aim to increase the knowledge about solar panels and their economic aspects by calculating and presenting payback periods for solar panels implemented in nonbuilding structures. In conjunction with this we also aim to present a basic theoretical background about solar panels and their global impact to further the understanding of the technology even more. On behalf of, and in collaboration with Trafikverket we have examined the payback periods of four solar panel installations in connection to four of the authority´s nonbuilding structures. Three of these solar installations are applied on technical buildings that are scattered alongside the railway system across the country. The solar panels provide local electricity to the electrical components within the building. The fourth solar installation is connected to a road tunnel where it provides local electricity to the lights within the tunnel. The conducted calculations have resulted in a payback period for each respective solar installation measured in years based on various relevant factors that influence their energy production. Our hope is that this can clarify the economic aspects of the solar panels and be of help in potential future investments in solar power by Trafikverket. The conclusion is that the solar panel installation connected to the road tunnel has the shortest payback period by far and also has great potential to be economically lucrative by generating future revenue. The tree solar installations connected to the technical buildings each have a significantly longer payback period but are still expected to be paid back eventually. However they are not expected to generate a mentionable yield, if any. / För att vi ska kunna förse Sverige och resterande delar av världen med energi på ett långsiktigt och hållbart sätt som tar hänsyn till de globala miljömålen krävs det att vi börjar använda mer förnyelsebara energikällor. Solceller och solenergi är en av dessa energikällor som har stor potential och tekniken har under de senaste decennierna blivit allt vanligare både i Sverige och i andra delar av världen. Allt från privatpersoner till företag och myndigheter gör i större och större utsträckning investeringar i tekniken. Med hjälp av litteraturstudier samt stöd från handledare syftar denna avhandling till att öka kunskapen om solceller och deras ekonomiska aspekter genom att beräkna och presentera återbetalningstider för solceller implementerade i anläggningskonstruktioner. I samband med detta kommer en grundläggande teoretisk bakgrund om solceller samt deras globala påverkan att presenteras för att öka förståelsen för ämnet ytterligare. På uppdrag av och i samarbete med Trafikverket har återbetalningstiden för fyra solcellsinstallationer i anslutning till myndighetens anläggningar undersökts. Tre av dessa är teknikhus längs med järnvägen utspridda i olika delar av landet där solcellsinstallationen bidrar med elektricitet till de tekniska komponenterna i huset. Den fjärde installationen ligger i anslutning till en vägtunnel där solcellsinstallationen bidrar med elektricitet till belysningen i tunneln. Resultatet av beräkningarna har gett en återbetalningstid i år för respektive installation baserat på diverse relevanta parametrar som påverkar elproduktionen. Vår förhoppning är att detta kan klargöra de ekonomiska aspekterna av solcellerna samt underlätta för Trafikverket att ta beslut om framtida potentiella solcellsinvesteringar i anslutning till deras anläggningar. Slutsatsen är att solcellsinstallationen i anslutning till vägnätet har den överlägset kortaste återbetalningstiden samt även god potential att bli ekonomiskt lukrativ. De tre installationerna i anslutning till teknikhusen har betydligt längre återbetalningstid och anses så småningom bli återbetalda men utan någon nämnvärd avkastning, om ens någon. / FoI Solenergi
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Fire Simulation Cost Reduction for Improved Safety and Response for Underground SpacesHaghighat, Ali 16 October 2017 (has links)
Over the past century, great strides have been made in the advancement of mine fire knowledge since the 1909 Cherry Mine Fire Disaster, one of the worst in U.S. history. However, fire hazards remain omnipresent in underground coal mines in the U.S. and around the world. A precise fire numerical analysis (simulation) before any fire events can give a broad view of the emergency scenarios, leading to improved emergency response, and better health and safety outcomes. However, the simulation cost of precise large complex dynamical systems such as fire in underground mines makes practical and even theoretical application challenging. This work details a novel methodology to reduce fire and airflow simulation costs in order to make simulation of complex systems around fire and mine ventilation systems viable. This study will examine the development of a Reduced Order Model (ROM) to predict the flow field of an underground mine geometry using proper orthogonal decomposition (POD) to reduce the airflow simulation cost in a nonlinear model. ROM proves to be an effective tool for approximating several possible solutions near a known solution, resulting in significant time savings over calculating full solutions and suitable for ensemble calculations. In addition, a novel iterative methodology was developed based on the physics of the fluid structure, turbulent kinetic energy (TKE) of the dynamical system, and the vortex dynamics to determine the interface boundary in multiscale (3D-1D) fire simulations of underground space environments. The proposed methodology was demonstrated to be a useful technique for the determination of near and far fire fields, and could be applied across a broad range of flow simulations and mine geometries. Moreover, this research develops a methodology to analyze the tenable limits in a methane fire event in an underground coal mine for bare-faced miners, mine rescue teams, and fire brigade teams in order to improve safety and training of personnel trained to fight fires. The outcomes of this research are specific to mining although the methods outlined might have broader impacts on the other fields such as tunneling and underground spaces technology, HVAC, and fire protection engineering industries. / Ph. D.
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